Hi All,

I recently had my car on a dyno and both the HP and torque lines were wavy when the secondary turbo came online. I've looked at several dyno results and read several threads trying to figure out what could be causing this (if abnormal).

Please take a look and see if this is "abnormal". If so, what could be causing this and how to solve. Ignition breakup?

redbase

 

get an HKS twin power

 

When breakup at higher rpm occurs, this is what it looks like on the dyno?

 

You sure you're not hitting fuel cut from overboost with the PFC? That graph kinda looks how it feels when you hit the PFCs fuel cut...

 

The reason the car was on the dyno was the PFC was being tuned. I had the turbo replaced with new 99 spec unit and the ASP med SMIC installed and fuel pump upgraded with the Denso unit (Supra). It was tuned to 14 lbs of boost. There was no mention of fuel cut off.

 

You need to know AFR to determine whether or not it is an ignition problem or a too rich/ lean condition.

 

I have attached the rest of the dyno results. The AFR is 15.05 and boost max is 13.76.

Will this help determine if it is fuel cut or ignition breakup?

 

lol, AFR is not 15. Looks like its between 11 and 12 but its hard to tell with that graph. If your AFR was 15, you would soon blow your motor.

It does look like ignition breakup to me. Possible solutions would be HKS twin power, quality plug cables, ignition coils. There might be others but thats what I remember offhand.

thewird

 

Thanks for your input. I just want to make sure I was putting my attention in the right area to resolve this. I have new plugs. I have debated on an ignition system for a little while but didn't think I needed one. Obviously, I might.

I'm trying for ~350rwhp. My next upgrade will be midpipe with retune of the PFC.